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CRR-20 & CRR-40, September 1999
µ
P-D Controller
Menu Pretrip Functions
4-25
Menu Pretrip Functions
Three pretrip test menus are available through the PTRIP
Menu of the controller to test the unit’s electrical and refriger-
ation system components.
1.
Extended Pretrip Test: Conducts a comprehensive func-
tional check of unit performance (requires up to 7 hours to
complete on an empty container). Activate an Extended
Pretrip Test (ETEST) from the PTRIP menu. When an
extended pretrip test is complete, unit operation stops.
The Extended Pretrip Test includes:
• Full Pretrip Test: Controller performs all of the tests
used in the Full Pretrip Test (see details below).
• Extended Cool Test: Controller operates unit in cooling
for an extended period to verify system cooling perfor-
mance. The extended test pulls the container tempera-
ture down to 0 C (32 F) and then -18 C (0 F) in two
stages.
2.
Full Pretrip Test: Conducts a functional check of unit
operating modes (requires up to 30 minutes to complete
on an empty container). Activate a Full Pretrip Test from
the PTRIP menu; or by pressing the PRETRIP key on the
controller keypad and then pressing the ENTER key.
When a full pretrip test is complete, the unit returns to
normal operation. The Full Pretrip Test includes:
• Display: Controller lights all segments in the display for
visual inspection by technician.
• Amps: Controller individually energizes all outputs
including fan and compressor motors, and solenoid
valves. The controller checks current draw to verify cor-
rect operation.
• Sensors: Controller operates unit to condition all sensors
and then verifies correct sensor calibration.
• Heat Capacity: Controller energizes evaporator fans and
electric heaters to verify correct operation.
• Defrost: Controller energizes electric heaters only to
verify correct defrost operation.
• Cool Capacity: Controller cycles unit through cooling
modes (including modulation) and monitors sensor tem-
peratures to verify correct refrigeration system operation.
3.
Single Pretrip Test: Conducts a functional check of one
of the individual operating modes conducted during a Full
Pretrip Test. Most tests require 1 to 10 minutes to com-
plete. However, COOL may take up to 30 minutes,
SENSR may take up to 45 minutes, and ECOOL may take
up to 7 hours. Activate a Single Pretrip Test from the
PTRIP menu. When a single pretrip test is complete, the
unit returns to normal operation.
NOTE: If a Check Alarm fault occurs during a
pretrip test, the Alarm LED turns ON while the
controller continues the Pretrip test. If a
Shutdown Alarm fault occurs during a Pretest
MENU PRETRIP Screen Flow Diagram (See Display Acronym Definitions on pages 4-4 to 4-6)
Содержание CRR-20
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